Lee M A, Liu Y
Defence Medical Research Institute, Clinical Research Centre, NUS, 10 Medical Drive #02-04, 117597, Singapore.
FEMS Microbiol Lett. 2000 Nov 1;192(1):67-72. doi: 10.1111/j.1574-6968.2000.tb09360.x.
Burkholderia pseudomallei, a Gram-negative bacterium is found in the soil and water, mainly in Southeast Asia and Northern Australia. It is responsible for melioidosis in human and animals. The bacteria produce several potential virulent factors such as extracellular protease, hemolysin, lipase and lecithinase. The isolation of virulence genes and the study of their functions will contribute to our understanding of bacterial pathogenesis. Previous studies have implicated protease as a contributing virulence factor in the pathogenesis of some bacteria. Three out of 5000 clones screened from a genomic DNA library of B. pseudomallei were found to express protease activity. The clones were found to have the same sequence. The nucleotide sequence revealed an open reading frame (designated as metalloprotease A, mprA) encoding a 500-amino acid protein, MprA, with an estimated molecular mass of 50241 Da. The predicted amino acid sequence shares homology with the subtilisin family of serine proteases.
类鼻疽杆菌是一种革兰氏阴性菌，存在于土壤和水中，主要分布在东南亚和澳大利亚北部。它可导致人类和动物患类鼻疽病。该细菌会产生多种潜在的毒力因子，如细胞外蛋白酶、溶血素、脂肪酶和卵磷脂酶。毒力基因的分离及其功能研究将有助于我们理解细菌的发病机制。先前的研究表明，蛋白酶是某些细菌发病机制中的一个致病因素。从类鼻疽杆菌基因组DNA文库筛选的5000个克隆中，有3个被发现具有蛋白酶活性。这些克隆具有相同的序列。核苷酸序列显示一个开放阅读框（命名为金属蛋白酶A，mprA），编码一个500个氨基酸的蛋白质MprA，估计分子量为50241 Da。预测的氨基酸序列与丝氨酸蛋白酶枯草杆菌蛋白酶家族具有同源性。
